Sound intensity level or acoustic intensity level is a logarithmic measure of the sound intensity (measured in W/m2), in comparison to a reference level.
The measure of a ratio of two sound intensities is
where I1 and I0 are the intensities.
The sound intensity level is given the letter "LI" and is measured in "dB". The decibel is a dimensionless quantity.
If I0 is the standard reference sound intensity
(W = watt), then instead of "dB SPL" we use "dB SIL". (SIL = sound intensity level).
Read more about this topic: Sound Intensity
Famous quotes containing the words sound, intensity and/or level:
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—Charles Dickens (1812–1870)
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“There is only one honest impulse at the bottom of Puritanism, and that is the impulse to punish the man with a superior capacity for happiness—to bring him down to the miserable level of “good” men i.e., of stupid, cowardly and chronically unhappy men.”
—H.L. (Henry Lewis)